Terminal bus of communicationSupported also ISO9141 protocolThis cable can not work if your car uses a protocol/ bussystem like VPW,PWM or Can-bus.Terminal L=Ignition for waking up car computing system (ECU: Engine Control Unit)Existed 3 different protocols with same OBD2 connector incl. ISO/KWP, VPW, PMWThis K/L Diaqnostic interface & cables work on ISO/KWP (Kev Word Protocol) Iaunched after 1996 only.The cables may work with some versions of the carsoft.Product running as virtual comport.